Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Design of A Asymmetric Branch Line Coupler Using Artificial Dielectric Substrate

가유전체 기판을 이용한 비대칭 브랜치 라인 커플러의 설계

  • Lim, Jong-Sik (Department of Electrical Engineering, Soonchunhyang University) ;
  • Lee, Jae-Hoon (Department of Electrical Engineering, Soonchunhyang University) ;
  • Kwon, Kyung-Hoon (Department of Electrical Engineering, Soonchunhyang University) ;
  • Ahn, Dal (Department of Electrical Engineering, Soonchunhyang University)
  • 임종식 (순천향대학교 전기공학과) ;
  • 이재훈 (순천향대학교 전기공학과) ;
  • 권경훈 (순천향대학교 전기공학과) ;
  • 안달 (순천향대학교 전기공학과)
  • Received : 2012.03.07
  • Accepted : 2012.05.10
  • Published : 2012.05.31
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Abstract

In this paper, the design of asymmetric branch line couplers using artificial dielectric substrate (ADS) is described. The effective permittivity and permeability increase in ADS because of the lots of the inserted via-holes. So the physical length and width of transmission lines realized on ADS are reduced compared to the standard lines. This enables one to design size-reduced microwave circuits. As an instance in this work, an asymmetric branch line coupler with the ratio of 3:1 is designed at 2GHz. The designed coupler has a small size of 53.4% compared to the normal circuit while the same performances are preserved. A good agreement between the simulated and measured asymmetric power dividing ratio is shown. The measured loss is only less than 0.2dB, which is a very small value.

본 논문에서는 가유전체 기판구조를 이용한 비대칭 브랜치 라인 커플러의 설계에 대하여 기술한다. 가유전체 기판구조에서는 주기적으로 다수의 비어홀들이 삽입되므로 등가적으로 유효유전율과 유효투자율이 증가하여, 여기에 전송선로를 구현할 경우 표준형 선로에 비하여 동일한 전기적 길이일 때 물리적 길이와 선폭이 감소하게 된다. 이런 특성을 이용하여 초고주파 회로들을 소형화하여 설계할 수 있는데, 본 논문에서는 2GHz대에서 동작하는 3:1 비대칭 브랜치 라인 커플러를 소형화하여 설계하는 것에 대하여 기술한다. 설계된 커플러는 표준형 전송선로를 이용하여 설계한 회로에 비하여 동일한 성능을 가지면서 약 53.4%의 크기를 갖는다. 비대칭 전력 분배 비율이 시뮬레이션과 측정 데이터에서 잘 일치하고 있으며, 측정된 손실도 불과 0.2dB 이내로 매우 적다.

Keywords

References

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